---Do you go to swim every day?---No but I .A. used to doB. usedC. used to do it soD. use

问题补充：

---Do you go to swim every day?

---No, but I .

A. used to do

B. used

C. used to do it so

D. used to

答案：

A. used to do

B. used

C. used to do it so

(答案→)D. used to

解析：根据题意，你每天去游泳吗？不，但是我过去每天去游泳。因此本题选D used to过去常常做某事。